The present invention relates, in general, to electronic sensing equipment and in particular to an optical position location apparatus for locating the position of an object along one or more coordinate axes and for determining other measurable parameters of the object.
There have been several devices in the past which have optically, or through a combination of mechanical and optical devices, had, as a purpose, the location of an object within a one- or two-dimensional frame of reference. Unfortunately, more recent attempts into the field of electro-optical "range finders" and/or "locators" have often been associated with problems which severly limit their effectiveness and use on a large scale. Two such devices are disclosed in U.S. Pat. application Ser. No. 3,184,847 of L. Rosen on a Digital Coordinate Resolver, and in the article Let Your Fingers do the Talking in Volume III, No. 8, BYTE Magazine, dated August, 1978, on a non-contact touch scanner.
Among the undesirable aspects of all the prior art, are the substantial costs involved with the unusually large number of components required to construct the devices into even a marginally operative apparatus. Reliance upon literally dozens of light emitting sources with equivalent numbers of "matched" photocell diodes has substantially limited the effectiveness and resolution of prior art optical scanners while, at the same time, requiring substantial expense in terms of costly electronic components which have made uses and applications of the devices impractical.
Other prior attempts have required the attachment of gratings, photocells, or other special paraphernalia to the object being located.
Similarly, the design of most prior art devices often proves to be difficult in terms of compatability with display devices which are capable of otherwise showing the results of the scanning operation. Moreover, where such display devices were utilized, the devices themselves required reinterpretation due to an inflexible, "non-linear" output of such devices.
Some prior art devices have required retroreflectors and, therefore, experience great difficulty locating reflective objects.
Prior art devices all too often relied upon less advanced optical techniques such as the Rosen device above, wherein parabolic mirrors, through their very nature require substantial size parameters. Additionally, great difficulty has been experienced in extending the capabilities of prior art devices beyond one or two dimensions, and few, if any, apparata have been capable of effectively resolving the location and other parameters of an object within a three-dimensional "corridor", or along three or more coordinate axes arranged in two dimensions. Moreover, prior art devices have suffered from limited spacial resolution and low scan rates, and, therefore, limited temporal resolution.
It is thus an object of the present invention to provide a substantially inexpensive optical position locator requiring a minimum of components which is substantially compact and lightweight and which, accordingly, is manufacturable in a facilitated manner in substantial volumes.
It is additionally an object of the present invention to provide such a position locator with substantial spacial and temporal resolution capabilities which is designed to quickly and accurately disclose parameters of an object located within its location region or "window".
It is another object of the present invention to disclose position and other parameters of ordinary untreated objects such as fingers, pens, or pencils.
It is further an object of the present invention to provide such an optical position location apparatus which is compatible with a variety of display outputs and which is capable of disclosing location information for either analysis by a user, or for further input into other systems, in a desirable fashion to avoid complex conversions, such as in linear fashion so as to avoid requiring trignometric conversion programs.
The present apparatus also has, among its objects, the object of providing such an efficient, low-cost, accurate location apparatus which, by its very design, is applicable for use in a myriad of applications ranging from computer information input (as a viable alternative to light pens and keyboards), to toys, automatic industrial machinery controls and any other uses, such as menu picking where expedited automatic determination of object parameters such as location, size and even speed, are required.
It is similarly an object of the present invention to be adaptable to analysis of a three-dimensional "corridor" and the location and other parameters of an object within that three-dimensional space through several different constructions, including the stacking of several two-dimensional units and/or reliance upon radiant energy intensity level analysis in a single two-dimensional unit which is capable of disclosing a third dimension of an object within its location region window. Yet, another embodiment utilizes three-dimensional distributors, collectors and selective viewing scanners.
It is also an object of the present invention to require a minimum of light or radiant energy emission sources and photo-detection devices through the utilization of a single radiant energy source with a novel rotating selective viewing scanner and associated detector which, in combination with novel electronic circuitry and a minimum of electronic components, accurately and quickly disclose the parameter information described above.
Yet, another object is to convert complex motions, such as those of human fingers in motion, into time varying signals to enable a person to so convey vast amounts of complex information to machines or other persons.
Another object is to replace switches.
These and other objects of the invention will become apparent in light of the present specification.